TWM479407U - Position signal capturing structure - Google Patents

Description

Position signal extraction structure

The present invention relates to a position signal extraction structure that can be applied to an optical ruler with high precision for repeatedly providing a drive actuator for accurate positive and negative voltage pulse signals.

Due to the miniaturization of electromechanical processing, precision positioning platforms have become indispensable instruments.

However, the displacement of the conventional detection platform is directly transmitted through the optical scale according to the displacement signal acquisition device, and then the grating is passed through the optical scale, and then the amplified signal (or the conversion mark point) is converted to generate the true displacement distance.

Since the signal acquisition device belongs to the Max trigger circuit (hard solution circuit), it is directly displayed on the optical scale. Therefore, the precise positioning platform control method or its system cannot effectively and accurately capture the displacement value of the actuator driving platform, so a large displacement error is generated.

The main purpose of the present invention is to provide a position signal acquisition structure capable of modifying the captured signal. The structure includes a pickup optical signal device capable of converting the optical scale signal into an actual moving distance, a displacement signal processor capable of capturing signals and values, a movement counter capable of converting the actual displacement distance, and two ends respectively Output loop point, mobile counter of telecom connection with load loop; borrowing multiple times to output loop point to load loop point, accumulating counter calculation to accurately output multiple times to the voltage pulse signal required to drive the actuator forward and reverse .

That is, the position signal extraction structure of the present invention transmits the signal output of the optical ruler through A displacement signal capture device allows the personal computer to capture the signal, and then according to the first threshold of the number of signals sent by the displacement signal processor, the number of signals is converted into a trigger number signal, and converted into a second threshold by the mobile counter, The second threshold signal is converted into a peak number signal output, and then the trigger number signal and the peak number signal are synthesized, and then processed into a corrected position signal output, and the corrected position signal is converted into a real position value. This real position value is immediately available to the actuator driver for updating its position information and determining whether a drive signal needs to be output. The driving period is composed of one or more voltage pulse signals whose frequency is driven by the actuator, and the intermittent signal maintains a zero voltage level during the rest period, so that the actuator does not during the rest period. Running.

The above as well as other objects, advantages and features of the present invention will be more fully understood and appreciated from the Detailed Description of the Detailed Description.

Please refer to the first figure, which is a schematic structural diagram of the present invention. The figure discloses a position signal capturing structure, which comprises: a sampling optical tape signal device, a displacement signal processor 2, and a mobile counter 3; An output loop point 4 and an input loop point 5. The optical tape signal device 1 can convert the optical tape signal of several gratings passing through an optical scale (not shown) into an actual moving distance, and the optical rule signal is an analog signal that can be captured by a computer; the displacement signal processor 2 is connected to the optical tape signal device 1 at one end, and can capture the grating signal and value corresponding to the movement of the optical ruler; the mobile counter 3 is connected with the displacement signal processor 2 to convert the actual distance of the platform movement into The value is outputted at one end of the output loop point 4 and connected to the mobile counter 3, and can output the actual distance after the platform moves; the end of the input loop point 5 is connected to the output loop point 4 by telecommunication, and the other end is connected to the displacement signal processor 2 by telecommunication.

By repeatedly outputting loopback point 4 to loading loopback point 5, via moving counter 3 The accumulating counter 35 calculates a precise multiple output to the voltage pulse signal required to drive the actuator forward and reverse.

The optical pickup signal device 1 is connected to the first oscilloscope 11 to display the numerical value. The moving counter 3 is connected to a second oscilloscope 36 to let the optical scale display the value. Moreover, the mobile counter 3 sequentially includes an array 31 electrically connected to the displacement signal processor 2, a peak counter 32 connected in series with the array 31, a numerical converter 33 electrically connected to the peak counter 32, and respectively The accumulating counter 35 is connected to the computer controllable converter 34, the output loop point 4, and the incoming loop point 5.

This embodiment, shown in the first figure, shows a schematic diagram of a specific embodiment of an automatic control structure of the present invention. The data capture card used in the optical tape signal device 1 is a data capture card produced by National Instruments, and the model number is PCI-6115. Since the output signal of the optical scale is a voltage pulse signal, it needs to be processed by the LabVIEW (signal control component) program signal to be converted into a position signal for use. The signal analysis of the optical scale is as shown in the second figure. When the output signal is a full-period square wave, it means that the platform moves 0.4 micron. The phase difference between the two sets of signals is a quarter of a cycle, indicating that the minimum resolution of the optical scale is 0.1 micron.

In the specific embodiment, the optical tape signal device 1 is obtained by the PCI-6115 data capture method, and the LabVIEW capture signal program is obtained, as shown in the first figure. The figure is divided into parts A, B and C, which are detailed below:

(a) Part A of the figure is the optical tape signal device 1 in which the signal data acquisition component characteristic is an adjustable signal data input range, and the mode and frequency (Hz) can be adjusted in the timing setting. Use the PCI-6115 signal data to capture the card's signal data to capture the maximum value function, and it needs to cooperate with the corresponding external junction box National Instruments' anti-alias input/output junction box.

(b) Part B of the figure is the displacement signal processor 2, so that the signal sent by the optical ruler is The square wave will generate up and down trigger signals. The function of the trigger signal gate of the displacement signal processor 2 can convert the trigger signal into the number of triggers, so that the optical scale can be recorded when the platform is moved to the platform. The number of square waves generated.

(c) Part C of the figure is the mobile counter 3, mainly the peak counter 32 and the numerical converter 33 and the second oscilloscope 36, wherein the peak counter 32 can only take the maximum number of peaks at the time of triggering; the array of the mobile counter 3 31 can convert the value into a matrix type, and display the accumulated result in a voltage pulse signal diagram of the optical ruler by using the cumulative method of counting (second picture); the second oscilloscope 36 signal display mode, which will be captured The optical ruler signal is selected to be displayed in the form of a square wave on the second oscilloscope 36, and the optical scale can display the value.

The setting frequency under the signal data acquisition component is mainly for the sampling frequency of the signal data acquisition card. In the present embodiment, since the actuator driving frequency is about 90 kHz, the sampling frequency is 500 kHz, and the sampling frequency is set to be about 5 times of the actuator driving frequency. According to the sampling theory, the optical should be sufficiently intercepted. The signal sent by the ruler. In the embodiment, the signal data capture mode is set to one tenth of a second, and the operation can be performed for the personal computer operation without losing too many platform mobile signals. It is conceivable that the above sampling frequency and batch transfer rate will differ depending on the application example, and therefore the numerical values given herein are merely examples and are not intended to limit the novel scope.

Since the optical scale is subject to external factors, it is necessary to process the signal of the optical ruler to determine what is the noise and eliminate it to get the correct position movement signal. In this embodiment, the function of filtering noise is achieved by the peak counter and the trigger signal gate function of the LabVIEW program shift processor. The displacement signal processor sets the signal gate value to ensure that the interference noise is not counted. The peak counter takes the peak signal mainly to ensure that the optical scale is high and low, and the oscillation is not switched. The processed signal takes the peak display signal, counts each point and calculates the correct platform movement position signal.

Since the loop time occurs when the program is executed, a solution is needed to avoid errors caused by the PC not being able to capture the correct signal when the program is executed.

In this embodiment, each time the LabVIEW program execution time is about 20 microseconds, the T _off (power off time) is set to be reserved for 100 microseconds, mainly to reserve 5 times of processing time to avoid platform movement in a short time. Long distances may cause a sudden increase in loop time and will not process all signals in time.

The above description of the specific embodiments of the present invention may be varied and modified without departing from the spirit of the novel as defined by the appended claims, and the broader scope of the claims. The principles of patent law within it are explained.

1‧‧‧Capture optical tape signal device

11‧‧‧First oscilloscope

2‧‧‧displacement signal processor

3‧‧‧Mobile counter

31‧‧‧Array

32‧‧‧ Peak Counter

33‧‧‧Numerical Converter

34‧‧‧Computer controllable converter

35‧‧‧Accumulate counter

36‧‧‧Second oscilloscope

4‧‧‧Output circle

5‧‧‧Into the loopback point

The first picture is a signal acquisition structure diagram; the second picture is a voltage pulse signal diagram of an optical scale.

1‧‧‧Capture optical tape signal device

11‧‧‧First oscilloscope

2‧‧‧displacement signal processor

3‧‧‧Mobile counter

31‧‧‧Array

32‧‧‧ Peak Counter

33‧‧‧Numerical Converter

34‧‧‧Computer controllable converter

35‧‧‧Accumulate counter

36‧‧‧Second oscilloscope

4‧‧‧Output circle

5‧‧‧Into the loopback point

Claims (5)

A position signal capture structure includes: a pickup optical signal device capable of converting an optical scale signal into an actual moving distance, the signal being an analog signal for reading by a computer; and a displacement signal processor having one end thereof The optical tape signal device is connected to the telecommunication device to capture the mobile signal and the value; a mobile counter is connected to the displacement signal processor at one end and can convert the actual distance into a numerical value; an output loop point, one end of which is connected with the mobile counter telecommunications The connection can output the actual distance; and one input loop point, one end of which is connected with the output loop point and the other end is connected with the displacement signal processor. For example, in the position signal extraction structure described in claim 1, the optical tape signal device is taken and connected to a first oscilloscope, so that the optical scale displays the value. The position signal extraction structure according to claim 1, wherein the mobile counter includes an array device electrically connected to the displacement signal processor, a peak counter connected to the array device, and a peak counter telecommunication connection. The value converter and the accumulating counter respectively connected to the computer controllable converter, the output loop point, and the incoming loop point telecommunications. For example, the location signal extraction structure described in claim 3, wherein the computer of the mobile counter can control the converter and connect to a second oscilloscope to display the value of the optical scale. For example, in the position signal extraction structure described in claim 1, wherein the movement counter is connected to a second oscilloscope, so that the optical scale displays the value.